Threading tool



June 5, 1923. 1,457,409

A. R. THOKE ET AL THREADING TOOL iiea March 1922 5 sheets-sheen w mma a;

L n, 43. & -7 V 5 Shecs-Shegt 4 THREADING TOOL Filed March 1922 I A. R; THOKE ET- AL June 5, 1923.

8 FIG 10 June 5, 1923.

I, v 1,457,409 A. RgTHOKE ET AL v THREADING 'IOOL I Filed March v. 1922 5 sheets she 'c 5 To all whom it may concern:

PatentedJune 5, 1923.

1...:UNITED} stares PATENT orrica.

ALBERT R. THOKE or PITTSBURGH. AND HUBERT 6. S ITH, 0F WILKINSBURG,

' PENNSYLVANIA.

'm'anfanmo T001).

Application filed March 7; 1922. "Serial No. 541,652.

Be it known'that we, ALBERT R. THOKE and HUBERT G. SMITH, citizens of. the United States, and residents of Pittsburgh and Wilkinsburg, respectively, in the county of Allegheny and btate of Pennsylvania, haveinvented anew and useful Improvement in Threading Tools; and we do hereby declare the following to be a full, clear, and exact-description thereof.

Our invention relates to a threading-tool, and particularly to die-heads of the type adapted for use in turrets and similarsupports of screw-threading machines.

The object of our invention is to provide a tool of.this character which is simple in construction and made up of a minimum number of parts and which will automatically retract the dies at the limit of their threading movement, as well as to improve such machines in other features.

In the accompanying drawings Fig. 1 is a front view of our improved tool; Fig. 2 is a section taken on the line 2-2, Fig. 1; Fig. 2 is an end view of the cam wrench; Fig. 3 is a crosssection taken on the line 33,' Fi 2; Fig. 4 is a section on the line 4-4, of *ig. 3; Fig. 5 is a half section corresponding to the upper half section of Fig. 2, showing'the threading-dies in their a vanced position; Fig. 6 is a section corresponding to the upper-half of Fig. 4. showing the threading dies in advanced position; Fig. 7 is a section taken diagonally opposite to the lower-half of Fig. 2; F 15;. 8

is a section corresponding to the upper-halt of Fig. 2 showing the threading dies withdrawn; Fig. 8 is a portion of the front of the tool with the threading-die in the position shown in Fig. 8; Fig. 9 is a view cor to the upper-half of Fig. 2. e threading-dies extended and respondin r showing iii expanded, the cam-ring having moved around to bring the roove of the cam over the threading die; of a portion of the tool showing the position of the partsof Fig. 9; Fig-.10 is a-vicw corrcspgnding to the upper part of Fig. 2, the threading-dies being drawn back on the cam-ring which is ready to be caught b? handor otherwise to put the ram-ring bac to the position of Fig. 1; and Fig. 11 is a sectional detail showing the worm and ig. 9 is a front view.

worm-wheel for operatingthe adjustment of the cam-ring for size adjustment.

The numeral 2 designates a suitable shell or casing ,which is screwed fast to the spindle 3. 'Within the shell 2 is the head or block 4, which has a slidin fit within the bore of the shell 2. The hea 4 is connected by'means of then-screws 6 to the chaser-block 5 The threading dies or chasers *7 are adapted to move in and out in guides in said chaser-block, and are secured to the block 8 by screws 9. The block 8 has the angular cam-slots 8 which are' engaged by the wedge-portions 10 of the die retracting membe 11 which surrounds the head 4 and has sliding engagement therewith. The die retracting member 11 is normally pressed forward by the springs 12, said springs fitting in a recess 13 in said member and interposed between the forward end of said seat and the enlargement 14 on the pin 15, the rear end of said enlargement engaging the shoulder 16 on thehead. There is only one pin 15, andin the other instances the rear ends of the springs l2 enter seats 17 in V the head 4.

The head 4 is provided with the recesses 18 to receive the springs 19, said sprin s being interposed between the rear ends 0 said recesses and the heads 20 of the bolts 21 connected to the shell or casing 2. The springs 19 act to hold back the head inormally in the position shown in Fig. 4.

Mounted on the shell 2 is the outer-shell or casing 22, and secured to said outer-casing, by means of the screws 24, is the camring 23 having the cam-faces 25 with the grooves 26, 26 formed at the ends thereof to'receive the threading dies, as will more fully hereinafter appear.

Formed in the, chasers or dies 7 are the notches 27 which normally register with the grooves 26, 26 formed in the cam-ring 23. The formation of the notches 27 in the dies 7 forms corresponding lugs 28 and 29, so

that when said dies are advanced to the posi- F ornied on the inner-shell 2 are the lugs 31 and on the outer she1l22 the lugs 32, the lugs 31 on the casing 2 entering the annular groove 34 formed in the outer-casing 22. Springs 35 are interposed between the lugs 31 and 32, said springs being'adapted to bring the outer-shell 22 and the cam-ring 23 back to normal position, as will more fully hereinafter appear.

At, the rear of the inner-casing 2, and interposed between said casing and the inwardly extending flange 36 of the outercasing, is the worm-wheel 37. A worm 38 journaled in the outer-casing 22 engages the worm-wheel 37, and as said worm-Wheel has the opening 39 which receives the outer end of the pin 15 it will be apparent that when the worm 38 is rotated the uter-casing will be turned to compress the springs 35.

' ually where desired, a cam 10 on the shaft 42 is adapted to engage the pin 43 extending through the outer casing 2 and adapted to bear against the inner end of the head 4.

The operation of our improved tool is as follows The threading dies 7 are first adjusted by turning the cam-ring 23 which is done by turning the worm 38, the cam-faces of said cam-ring being in engagement with the threading-dies, said dies will be moved inwardly in proportion to the amount of rotary movement imparted to the cam-ring 23. \Vhen the cam-ring has been adjusted so as to bring the dies into proper position for threadin the work, the work is rotated and the spin le 3 carrying the threading tool;is held from rotation or vice versa but is advanced longitudinally and the thread is formed on the work. When the length of thread desired has been formed the spindle 3 is reversed by suitable reversing mechanism or stopped, and the threading-tool st-artsto withdraw, or dies continue to advance due to the thread, the threads of the.

blocks 8 force said blocks outwardlv, drivin r e the lugs 30 intothe grooves 20 and the lugs '29 into the groove 26. bringing the parts into the position shown in Fig. 8. 3y the forward movement of the die-blocks 5 the head twill be advanced, putting the springs 19 under compression, and at the same time the pin 15 is withdrawn from engagement with theworm-wheel 87, as shown in Fig. 5. The springs 35 which have been compressed by the previous adjusting of the cam-ring 23 to bring the threading-dies into proper position, now act to return said cam ring to the position shown in Figs. 9, 9 bringing the threading-dies into register with the notches 26" at the ends of the cam-faces 25 shown in Fig. 9.

The outer shell is then turned by the bandle 45 in a reverse direction to that which was imparted to it by the springs 35. This rotary movement is continued until hole 36 is brought into alignment with pin 15, at

which instant the pin 15, actuated by springv 12 in piece 10, plunges into the opening 39 and thus relocates cam-rlng in original position and consequently restores setting of die able in and out in said die-blocks, notches" formed in said dies forming lugs adapted to engage grooves tormed In said cam-ring'and the front face of sald ring when said dies are advanced beyond the face of. saidcam-- ring, means for retracting said dies, and means for automatically turnin said camring when said dies are advanced.

2. In a threading-tool, the combination of a suitable casing,a spring actuated camring having rotary relation with said casmg, a spring actuated slidable head in said casing, die-blocks connected to said head, dies movable in and out in said die-blocks. notches formed in said dies forming lugs adapted to engage grooves formed in said cam-ring and the frontface of said ring when said dies areadvanced beyond the face of said cam-ring, and means for retracting said dies. 1

3. In a threading-tool, the combination of a suitable casing, an outer casing surrounding said first casing, a cam-ring connected to'said outer casing, stops on said inner-casing, stops on said outer-casing,

springs interposed between the stops -on said outer-casing and the stops on said inner-casing, means for rotating said outercasing, a spring actuated slidable head in said casing, die-blocks connected to said head, dies movable in and out in said dieblocks, means for bringing said dies into inter-engaging relation with said cam-ring when said dies are advanced, and means for retracting said dies.

4.-In a threading-tool, the combination of a suitable casing, an outer casing surrounding said first named casing, a .camring connected to said outer casing, stops .on said inner and ontercasings, springs engaging the stops on said inner and outercasings, a worm-wheel on said inner casing, a worm in said outer-easing engaging said worm-wheel, whereby said outer easing is rotated to compress said springs, a spring actuated slidable head in said inner-easing.

a bolt on said head engaging an opening in said worm-Wheel, die-bloehs connected to said head, dies movable in and out in said die blocks, means for bringing said dies into interengaging relation with said ram-ring when said dies are advanred beyond said cam-ring. whereby said head is likewise adranred and said bolt is withdrawn from said, worm-wheel to permit said outer-casing rarrying said ram-ring to rotate.

5. In a .tlireadirig-tool the combination of a suitable easing. a spring artuated earnring having rotary relation with said (asing. a spring a tualed slidahle head in said easing. die-hlovlcs rennet-ted to said head dies movable in and out of said die-hlocks, means for bringing said dies into interengaging relation with said am-ring when said dies are advanced and spring actuated Wedge-members adapted to engage said dies to retract the same hen said dies are advaneed.

(3. ln a threading-tool, the combination oi" a suitable easing, a spring actuated caniring having rotary relation with said easing, a spring actuated slidahle head in said easing die-blocks connected to' said. head, dies movable in and out in said die-blocks, hlovhs ronnevted to said dies haring heveled fares and openings formed thereixn spring aetuat-ed wedge menibers adapted to engage said heveled faces and enter said openings, means for bringing said dies and said camring mto interengagmg relation when said dies are advanced, whereby when said dies are mlranced said spring actuated-wedgemenihers advance, engaging said beveled fares oi said blocks to retract said dies.

In testimony whereof, we, the said AL- nlcn'r It. 'inolui and llmnnrr (i. SMITH have hereunto set ur hands.

' ALBERT R. THOKE. HUBERT G. SMITH. 'itnesses JonN F. VVILL, HENRY HoLz. 

